Knowledge Test Class B #1
Class B Driving Test | Iowa 2025 #1 Page 4 of 7
Train for FREE online with our Iowa class B license test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a IA CDL class B permit in 2025, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that CDL class B requirements may vary from state to state.
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22 . During a static leakage test, what is the maximum leakage rate that is safe for a double combination vehicle?
When performing a static leakage test on a double combination vehicle with air brakes, the leakage rate should be no more than 3 psi in one minute. If the air leaks from the air brake system at a quicker rate, the vehicle should not be driven because something likely needs to be repaired.
23 . When driving:
You should always use turn signals to warn others about your intentions.
It is important to communicate your intentions to others on the road. Make sure to signal before turning or changing lanes, even if no other vehicles are nearby.
24 . When transporting a load, you should inspect the cargo:
Cargo and its securement must be inspected every time you take a break during a trip. Be sure to inspect the cargo at least every 150 miles.
25 . A low air pressure warning signal should activate:
When tank pressure falls below 5 psi.
In an air brake system, a low air pressure warning signal must come on if air pressure in the tanks falls below 60 psi. This warning signal may come in the form of a light, a buzzer, or a wig wag.
26 . Which of the following is not a cause of hydraulic brake failure?
Most cases of hydraulic brake failure come from one of two causes. The brakes may fail due to a loss of hydraulic pressure or due to overuse on long hills, causing the brakes to fade.
27 . Operating a CMV with any measurable amount of alcohol in your system will result in an out-of-service order for:
One year.
If you are found to be driving with any detectable amount of alcohol in your system, but are still below the legal limit of 0.04 percent, you will put out-of-service for a period of 24 hours.
28 . Watching the road ahead of you:
Always watch for hazards on the road ahead. Doing this will allow you time to react to hazards before meeting them.
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2025 Iowa | Frequently Asked Questions
To secure a CDL Bus endorsement in Iowa, you must first hold a valid Commercial Driver's License (CDL). You then need to pass the Passenger Transport Test, undergo a physical examination, and complete a skills test in the type of vehicle you'll be driving. Finally, you must pass a background check as mandated by Federal Motor Carrier Safety Administration.
To obtain a CDL Bus license, you must first have a valid driver's license. Then, pass the CDL general knowledge test, and the passenger transport test. You must also pass a physical examination and a skills test in the type of bus you will be driving. Finally, submit to a background check as required by the Federal Motor Carrier Safety Administration.
Yes, specific training is necessary for a CDL Bus endorsement. You must complete a commercial driver's education course, pass the general knowledge and passenger transport written tests, and successfully complete a skills test in the type of bus you'll be driving. Some states also require applicants to have a certain amount of driving experience.
CDL Bus licenses are classified into three main categories: Class A, B, and C. Class A is for vehicles with a combined weight over 26,001 lbs where the vehicle being towed is over 10,000 lbs. Class B is for single vehicles over 26,001 lbs not towing a vehicle over 10,000 lbs. Class C is for vehicles carrying 16 or more passengers including the driver or hazardous materials.
No, you cannot use your personal vehicle for the CDL Bus driving test. The test must be taken in the same type of vehicle for which you are trying to get licensed. This means you will need to take the test in a commercial bus similar to the one you will be driving professionally.
During the CDL Bus driving test, you'll be evaluated on several skills. These include pre-trip vehicle inspection, basic vehicle control (backing, turning, stopping), and on-road driving (including highway, city, and residential driving). You'll also be tested on specific bus maneuvers such as loading and unloading passengers, bus stop procedures, and emergency exit procedures.
Yes, there are additional medical prerequisites for a CDL Bus endorsement. You must pass a Department of Transportation (DOT) physical exam every 24 months. The exam assesses hearing, vision, blood pressure, and checks for conditions like diabetes or epilepsy that could affect your ability to safely operate a bus.
No, it's not permissible to transport passengers without a valid CDL Bus endorsement in Iowa. It's a requirement by law for drivers who operate a vehicle designed to carry 16 or more passengers, including the driver. Driving such a vehicle without the proper endorsement could result in serious legal consequences, including fines and suspension of your driving privileges.
Yes, the CDL Bus endorsement can be added to your existing CDL in Iowa. You don't need to apply for a new license, but you must pass the Passenger Transport test. Once you pass, the endorsement will be added to your current CDL. However, you may need to renew your license if it's close to its expiration date.
Yes, drivers with a CDL Bus endorsement must comply with federal and state regulations. These include maintaining a logbook of hours driven, undergoing regular medical examinations, and adhering to restrictions on alcohol consumption. Also, some states may have additional restrictions such as age limits and mandatory rest periods between driving shifts.
